The present invention relates to an apparatus for preparing an end of a strand of textile material built into a package.
A primary objective of a strand or yarn end preparation process is the relatively fast, non-damaging placement of the strand or yarn end on the package in a preferred disposition for ready engagement of the strand or yarn end at a winding station of a winding machine. In U.S. Pat. No. 4,681,271, a yarn end preparation device is disclosed which includes a conduit having a slot formed therein for applying a suction to a yarn package to thereby engage a yarn end of the package and subsequently unwind the yarn end which is subsequently disposed in proper position for engagement at the winding station.
In German Auslegeschrift No. 18 06 672, a yarn end preparation device is disclosed which includes a pair of parallel rotating rollers. A yarn package to be prepared is disposed in axial alignment with the rotatable rollers with its outer surface in engagement with the rollers and the rollers are rotated to effect corresponding unwinding rotation of the yarn package. A pneumatic suction apparatus is disposed between the rotating rollers to apply suction to the rotating yarn package to thereby engage a yarn end thereof and to draw the yarn end from the yarn package. The suction apparatus includes a sensor for sensing the travel therepast of an unwound yarn end and a yarn cutting device is actuated in correspondence with the sensing of the unwound yarn end to cut the yarn end. In correspondence with the cutting of the yarn end, the yarn package is axially moved relative to the rotating rollers to position the top portion of the yarn package relative to the suction device for rewinding of the unwound yarn end onto the top portion of the package. The repositioning of the yarn package relative to the suction device is necessary because the yarn end engaged by the suction device typically enters the opening of the suction device at the same relative axial location at which the yarn end is dislodged from the outer surface of the yarn package.
However, the need exists for improvements in yarn end preparation devices of the type which unwind a yarn end from a yarn package and subsequently support the unwound yarn end while the yarn end is rewound onto the yarn package at a preferred axial location thereon. For example, in the yarn end preparation device disclosed in U.S Pat. No. 4,681,271, the conduit slot extends beyond the yarn package and this leads to a relatively high suction flow requirement as well as a less than optimum application of suction force to the yarn package. In those yarn end preparation devices of the type in which the yarn package is axially shifted to align the yarn package for rewinding of an unwound yarn end onto the package, devices capable of relatively complex movements must be provided to handle those yarn packages delivered to the yarn end preparation device which are individually supported on package support members.
Accordingly, the need exists for a yarn or strand end preparation apparatus which reliably prepares the strand or yarn ends of yarn packages supported in upright dispositions on individual package support members in which the strand or yarn end preparation apparatus optimally applies suction force to the yarn package and which performs the strand end preparation process without the need to axially shift the yarn package.